Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	$ 177,227	$ 185,250
Investment securities available for sale, gross unrealized gains	2,097	2,400
Investment securities available for sale, gross unrealized losses	(3,182)	(2,271)
Investment securities available for sale, at fair value	176,142	185,379
Investment securities held to maturity at amortized cost	119,338	67,866
Investment securities held to maturity, gross unrealized gains	446	531
Investment securities held to maturity, gross unrealized losses	(515)	(144)
Investment securities held to maturity, at fair value	119,269	68,253
Collateralized Mortgage Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	92,324	98,626
Investment securities available for sale, gross unrealized gains	768	692
Investment securities available for sale, gross unrealized losses	(918)	(96)
Investment securities available for sale, at fair value	92,174	99,222
Investment securities held to maturity at amortized cost	103,851	67,845
Investment securities held to maturity, gross unrealized gains	445	531
Investment securities held to maturity, gross unrealized losses	(444)	(144)
Investment securities held to maturity, at fair value	103,852	68,232
Collateralized Mortgage Backed Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	11,476	13,271
Investment securities available for sale, gross unrealized gains	457	564
Investment securities available for sale, gross unrealized losses	(74)	(33)
Investment securities available for sale, at fair value	11,859	13,802
Investment securities held to maturity at amortized cost	8,168
Investment securities held to maturity, gross unrealized gains	1
Investment securities held to maturity, gross unrealized losses	(25)
Investment securities held to maturity, at fair value	8,144
US States and Political Subdivisions Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	20,345	15,784
Investment securities available for sale, gross unrealized gains	249	363
Investment securities available for sale, gross unrealized losses	(237)	(40)
Investment securities available for sale, at fair value	20,357	16,107
Corporate Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	31,336	33,840
Investment securities available for sale, gross unrealized gains	359	621
Investment securities available for sale, gross unrealized losses	(333)	(34)
Investment securities available for sale, at fair value	31,362	34,427
Asset-backed Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	18,005	18,353
Investment securities available for sale, gross unrealized gains	259	152
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	18,264	18,505
Collateralized Debt Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	3,626	5,261
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(1,620)	(2,068)
Investment securities available for sale, at fair value	2,006	3,193
Other Debt Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	115	115
Investment securities available for sale, gross unrealized gains	5	8
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	120	123
Investment securities held to maturity at amortized cost	20	20
Investment securities held to maturity, gross unrealized gains	0	0
Investment securities held to maturity, gross unrealized losses	0	0
Investment securities held to maturity, at fair value	20	20
US Government Agencies Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities held to maturity at amortized cost	7,299	1
Investment securities held to maturity, gross unrealized gains	0	0
Investment securities held to maturity, gross unrealized losses	(46)	0
Investment securities held to maturity, at fair value	$ 7,253	$ 1

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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